Silver halide and polymerizable compound containing light-sensitive layer provided on support of defined roughness

ABSTRACT

A light-sensitive material comprising a light-sensitive layer which contains silver halide, a reducing agent and a polymerizable compound provided on a porous support wherein the porous support has such a surface characteristic that a filtered maximum waviness of not less than 4 μm is observed in not more than 20 positions among 100 positions which are determined at random on a filtered waviness curve. The filtered maximum waviness is determined within basic length of 2.5 mm extracted from the filtered waviness curve which is obtained from the profile of the porous support under the condition of the cut-off value of 0.8 mm according to JIS-B-0610.

BACKGROUND OF THE INVENTION

1. Field of the invention

This invention relates to a light-sensitive material comprising alight-sensitive layer containing silver halide, a reducing agent and apolymerizable compound provided on a support and an image-formingmethods employing the same.

2. Description of prior arts

Light-sensitive materials comprising a light-sensitive layer containingsilver halide, a reducing agent and a polymerizable compound provided ona support can be used in an image forming method in which a latent imageof silver halide is formed, and then the polymerizable compound ispolymerized to form the corresponding image.

Examples of said image forming methods are described in Japanese PatentPublication Nos. 45(1970)-11149 (corresponding to U.S. Pat. No.3,697,275), 47(1972)-20741 (corresponding to U.S. Pat. No. 3,687,667)and 49(1974) -10697, and Japanese Patent Provisional Publication Nos.57(1982)-138632, 57(1982)-142638, 57(1982)-176033, 57(1982)-211146(corresponding to U.S. Pat. No. 4,557,997), 58(1983)-107529(corresponding to U.S. Pat. No. 4,560,637), 58(1983)-121031(corresponding to U.S. Pat. No. 4,547,450) and 58(1983)-169143. In theseimage forming methods, when the exposed silver halide is developed usinga developing solution, the polymerizable compound is induced topolymerize in the presence of a reducing agent (which is oxidized) toform a polymer image. Thus, these methods need a wet development processemploying a developing solution. Therefore, the process takes arelatively long time for the operation.

An improved image forming method employing a dry process is described inJapanese Patent Provisional Publication Nos. 61(1986)-69062 and61(1986)-73145 (the contents of both publications are described in U.S.Pat. No. 4,629,676 and European Patent Provisional Publication No.0174634A2). In this image forming method, a recording material (i.e.,light-sensitive material) comprising a light-sensitive layer containinga light-sensitive silver salt (i.e., silver halide), a reducing agent, across-linkable compound (i.e., polymerizable compound) and a binderprovided on a support is imagewise exposed to form a latent image, andthen the material is heated to polymerize within the area where thelatent image of the silver halide has been formed. The above methodemploying the dry process and the light-sensitive material employablefor such method are also described in Japanese Patent ProvisionalPublication Nos. 61(1986)-183640, 61(1986)-188535 and 61(1986)-228441.

The above-mentioned image forming methods are based on the principle inwhich the polymerizable compound is polymerized within the area where alatent image of the silver halide has been formed.

Japanese Patent Provisional Publication No. 61(1986)-260241 describesanother image forming method in which the polymerizable compound withinthe area where a latent image of the silver halide has not been formedis polymerized. In the method, when the material is heated, the reducingagent functions as polymerization inhibitor within the area where alatent image of the silver halide has been formed, and the polymerizablecompound within the other area is polymerized.

Further, Japanese Patent Provisional Publication No. 61(1986)-73145(corresponding to European Patent Provisional Publication No. 0174634A2)describes an embodiment of the image-forming methods which comprises:imagewise exposing a light-sensitive material comprising alight-sensitive layer provided on a support wherein the light-sensitivelayer contains silver halide, a reducing agent and a polymerizablecompound; simultaneously or thereafter developing the light-sensitivematerial; and pressing the light-sensitive material on animage-receiving material to transfer the unpolymerized polymerizablecompound to the image-receiving material.

As the support of the light-sensitive material, a porous sheet isfrequently employed, because the porous sheet is light-weight and it iseasy to form the light-sensitive layer on the porous sheet. In the casethat the unpolymerized polymerizable compound is transferred from thelight-sensitive material employing the porous support to theimage-receiving material under certain conditions, low density spots ofdiameter of about 10 μm to about 1 mm containing an extremely smallamount of the unpolymerized polymerizable compound are sometimes formedon the image-receiving material within the area where the polymerizablecompound should be placed.

The above spot can be minimized by employing a thick sheet as thesupport, but the thick light-sensitive material is not preferred inconsideration of handling in the image formation, space required for thestorage of the material and the cost for preparation thereof.Alternatively, the above spot can be also minimized when the image istransferred under high pressure, but it brings about requirement thatthe pressure device should be more powerful than the conventional one toobtain such high pressure.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a light-sensitivematerial which is minimized or reduced in the occurrence of the abovelow-density spot in the image formation.

There is provided by the present invention a light-sensitive materialcomprising a light-sensitive layer provided on a porous support whereinthe light-sensitive layer contains silver halide, a reducing agent and apolymerizable compound, characterized in that the porous support hassuch a surface characteristic that a filtered maximum waviness of notless than 4 μm is observed in not more than 20 positions among 100positions which are determined at random on a filtered waviness curve.The filtered maximum waviness is determined within basic length of 2.5mm extracted from the filtered waviness curve which is obtained from theprofile of the porous support under the condition of the cut-off valueof 0.8 mm according to JIS-B-0610.

The light-sensitive material of the invention can be advantageously usedin a process which comprises:

imagewise exposing a light-sensitive material to form a latent image ofthe silver halide;

simultaneously or thereafter developing the light-sensitive material topolymerize the polymerizable compound within the area where the latentimage of the silver halide has been formed (or the area where the latentimage of the silver halide has not been formed); and

pressing the light-sensitive material on an image-receiving material totransfer the obtained image to the image-receiving material.

The light-sensitive material of the invention is characterized that theporous support has such a surface characteristic that a filtered maximumwaviness of not less than 4 μm is observed in not more than 20 positionsamong 100 positions which have been chosen at random on the filteredwaviness curve.

The present inventor has found that the above-mentioned low-density spotwhich occurs on a transferred image from the light-sensitive materialemploying a porous support can be much minimized or reduced byincreasing the surface smoothness of the porous support on the sidefacing the light-sensitive layer.

In the light-sensitive material of the invention, the porous support hasthe above-defined smooth surface characteristic. Therefore, thelight-sensitive material gives an improved clear image in which theoccurrence of the above low-density spot in the image formation is muchminimized or reduced. Further, the light-sensitive material of theinvention has an advantage of more easily and inexpensively solving theproblem with respect to the low-density spot, as compared with themeasures employing a thick porous support or a powerful pressure device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 represents a portion of a typical profile curve of a poroussupport.

FIG. 2 represents a part of a typical filtered waviness curve which isobtained from the profile curve shown in FIG. 1.

FIG. 3 is given to illustrate the method for the determination of thefiltered maximum waviness.

DETAILED DESCRIPTION OF THE INVENTION

Japanese Industrial Standard (JIS) B 0610-1976 specifies the system ofrepresentation of surface waviness by filtered maximum waviness(W_(CM)).

The principle terms used in this standard are defined as follows.

Surface waviness: Each arithmetic average of values of W_(CM) measuredat several positions which have been chosen at random on a machinesurface. Generally, on a machine surface, surface waviness at individualpositions is not uniform but usually presents considerably largedispersion. Therefore, the determination of the waviness of a machinesurface requires the selection of the measuring positions and a numberwhich will lead to obtain the efficient estimation of the populationmean. When the object of measurement permits, it is allowed to make thevalue obtained at one position of the machine surface to represent theoverall surface waviness. Profile is a contour which is presented on asectional plane when a surface to be measured has been cut by a planeperpendicular to the mean surface of the surface to be measured. In thecase where the profile is obtained by the stylus method, the radius ofcurvature of the stylus tip shall be sufficiently small, generally, 12.5μm or under. However, for the purpose of measuring the surface wavinessonly, the radius of curvature of the stylus tip may be about 30 μm atthe largest. In the case where the profile is obtained by the stylusmethod using a skid as the guide, the radius of curvature of the skidemployed shall be sufficiently large. Where the skewness of the profilecaused by the use of a skid causes trouble, the relative position of theskid and the stylus and the radius of the curvature of the skid shall beclearly noted.

A filtered waviness curve is a curve obtained by removing the shortwavelength components of surface roughness from the profile.

The cut-off value of filtered waviness curve is defined as follows: Inthe case where the filtered waviness curve is to be obtained, awavelength corresponding to the frequency at which its gain becomes 70%when a low-pass filter of an attenuation rate of -12 dB/oct is used.

The basic length of a filtered waviness curve is the length of a portionextracted from the filtered waviness curve by a fixed length (the basiclength).

The maximum waviness is the maximum height of a wave of a portionextracted as long as the basic length from the filtered waviness curveexpressed in micrometer units (μm) and is defined as the filteredmaximum waviness (W_(CM)). In the case where the surface to be measuredis a curved surface, the filtered maximum waviness is to be obtainedalong a curve which is expected to appear on its section.

The light-sensitive material of the present invention employs an poroussheet as the support. Examples of the porous sheet include not only apaper (including a coated paper and a synthetic paper), but also anon-woven fabric, a woven fabric and a knitted fabric.

In the present invention, the porous support has such a surfacecharacteristic at least on the side facing the light-sensitive layerthat a filtered maximum waviness of not less than 4 μm is observed innot more than 20 positions among 100 positions which have been chosen atrandom on the filtered waviness curve. The filtered maximum waviness isdetermined within basic length of 2.5 mm extracted from the filteredwaviness curve which is obtained from the profile (namely profile curve)of the porous support under the condition of the cut-off value of 0.8 mmaccording to JIS-B-0610.

The profile curve means a contour which is presented on a sectionalplane, when a surface to be measured has been cut by a planeperpendicular to the mean surface of the surface to be measured. Thefiltered waviness curve is a curve obtained by removing the short wavelength components of surface roughness by a low band filter from theprofile curve. The cut-off value means a wave length corresponding tothe frequency at which its gain becomes 70% when a low-pass filter ofattenuation rate of -12 dB/oct is used, in the case where the filteredwaviness curve is to be obtained. Further, the filtered maximum waviness(W_(CM)) means a maximum height of wave of a portion within the basiclength (L) extracted from the filtered waviness curve, expressed inmicrometer unit (μm).

The filtered maximum waviness with a high band cutoff value is hereinused as the expression of the unevenness (or smoothness) on the surfaceof a support, because the occurrence of the above-mentioned low-densityspot is scarcely influenced by the unevenness in which the wavelength isshorter than 0.8 mm. The present inventor has determined that the basiclength is 2.5 mm, because the occurrence of the above-mentionedlow-density spot is also scarcely influenced by the unevenness in whichthe wavelength is longer than 2.5 mm. These tendencies are remarkable inthe case that the thickness of the support is not more than 100 μm.

These definitions are further described hereinafter by referring to theaccompanying drawings.

FIG. 1 represents a part of a typical profile of a porous support. Theprofile has been obtained by the stylus method according to JIS-B-0610on a support made of a fibrous material.

FIG. 2 represents a part of a typical filtered waviness curve which isobtained using a low band filter having a cut-off value of 0.8 mm fromthe profile shown in FIG. 1.

FIG. 3 is given to explain the method for the determination of thefiltered maximum waviness in which the (L) is the basic length. As shownin FIG. 3, the part having the length (L) is extracted at random formthe filtered waviness curve (a), and the mean line (b) is determinedwithin the above part of the filtered waviness curve. The mean line (b)is a straight line at which the total square of the difference betweenthe straight line and the filtered waviness curve becomes smallest. Thefiltered maximum waviness (W_(CM)) means the sum of the differencesbetween the wave height of the highest wave and the mean line andbetween the wave height of the lowest wave and the mean line.

The light-sensitive material of the invention is characterized that theporous support has such a surface characteristic at least on the sidefacing the light-sensitive layer that when a filtered maximum wavinessis thus measured in 100 positions which have been chosen at random onthe filtered waviness, the filtered maximum waviness of not less than 4μm is observed in not more than 20 positions. More preferably, thefiltered maximum waviness of not less than 4 μm is observed in not morethan 5 positions.

The light-sensitive material of the invention uses a porous sheet havingthe above mentioned surface characteristic as the support. This poroussheet is commercially available. Otherwise the porous sheet can beprepared from a conventional porous sheet with an adequate treatment.

A pressure treatment, such as calendering can give the surfacecharacteristic to the generally available porous sheet. More generally,the surface characteristic can be given to the porous sheet by coating apaint on one side or both sides of the sheet.

For example, a coated porous paper can be used as the support of thelight-sensitive material of the invention. The coated paper is generallyobtained by coating a paint, in which a mineral pigment (e.g., Chinaclay) and an adhessive (e.g., casein, starch, latex, polyvinyl alcoholand the mixture thereof) is mixed, on one side or both sides of a basepaper (e.g., wood free paper, fine paper). The coated paper can beclassified into an art paper (amount of the coated paint; about 20g/m²), a coat paper (about 10 g/m²) and a lightweight coated paper(about 5 g/m²) according the amount of the coated paint. Further, thecoated paper include a cast-coated paper which shows a strong grossgiven by pressing the coated surface on a specular face of a drier whilethe plasticity of the coated paint still remains. Details of the coatedpaper are described in "Handbook of Paper and Pulp Technology" edittedby the Assosiation for paper and pulp technology in Japan (1982), pp.415, 535-536. Among the coated papers, the cast-coat paper is mostpreferred.

The coated paper preferably has a basis weight of from 20 g/m² to 200g/m², more preferably from 50 g/m² to 100 g/m².

Typical example of the porous sheet having the above mentioned surfacecharacteristic without any treatment is a synthetic paper. The syntheticpaper is generally obtained by forming a sytnthetic high polymercompound to have properties of paper. Examples of the synthetic papersinclude a synthetic fiber paper and a plastic film paper. The method forthe preparation of the synthetic paper is classified into a fiber basemethod and a film base method according to the form of the low material.The film base method is classified into a coating method, a solventtreating method in which etching is employed, an emboss method and ablend method in which an opaque pigment is employed, according to thetreatment process.

The silver halide, the reducing agent and the polymerizable compoundwhich constitute the light-sensitive layer provided on theabove-mentioned support are stated below. Thus composed material isreferred hereinafter to as "light-sensitive material".

There is no specific limitation with respect to silver halide containedin the light-sensitive layer of the light-sensitive material.

Examples of the silver halides include as silver chloride, silverbromide, silver iodide, silver chlorobromide, silver chloroiodide,silver iodobromide, and silver chloroiodobromide in the form of grains.

The halogen composition of individual grains may be homogeneous orheterogeneous. The heterogeneous grains having a multilayered structurein which the halogen composition varies from the core to the outer shell(see Japanese Patent Provisional Publication Nos. 57(1982)-154232,58(1983)-108533, 59(1984)-48755 and 59(1984)-52237, U.S. Pat. No.4,433,048, and European Pat. No. 100,984) can be employed.

There is no specific limitation on the crystal habit of silver halidegrains. Two or more kinds of silver halide grains which differ inhalogen composition, crystal habit, grain size, and/or other featuresfrom each other can be used in combination. There is no specificlimitation on grain size distribution of silver halide grains. Thesilver halide grains ordinarily have a mean size of 0.001 to 5 μm, morepreferably 0.001 to 2 μm.

The total silver content (including silver halide and an organic silversalt which is one of optional components) in the light-sensitive layerpreferably is in the range of from 0.1 mg/m² to 10 g/m². The silvercontent of the silver halide in the light-sensitive layer preferably isnot more than 1 g/m², more preferably in the range of from 1 mg to 500mg/m².

The reducing agent employed in the light-sensitive material has afunction of reducing the silver halide and/or a function of acceleratingor restraining a polymerization of the polymerizable compound. Examplesof the reducing agents having these functions include various compounds,such as hydroquinones, catechols, p-aminophenols, p-phenylenediamines,3-pyrazolidones, 3-aminopyrazoles, 4-amino-5-pyrazolones,5-aminouracils, 4,5-dihydroxy-6-aminopyrimidines, reductones,aminoreductones, o- or p-sulfonamidophenols, o- orp-sulfonamidonaphthols, 2-sulfonamidoindanones,4-sulfonamido-5-pyrazolones, 3-sulfonamidoindoles,sulfonamidopyrazolobenzimidazoles, sulfonamidopyrazolotriazoles,α-sulfonamidoketones, hydrazines, etc. Depending on the nature or amountof the reducing agent, the polymerizable compound in either a portionwhere a latent image of the silver halide has been formed or a portionwhere a latent image of the silver halide has not been formed can bepolymerized. In the developing system in which the polymerizablecompound in the portion where the latent image has not been formed ispolymerized, 1-phenyl-3-pyrazolindone is preferably employed as thereducing agent.

The light-sensitive materials employing the reducing agent having thesefunctions (including compounds referred to as developing agent orhydrazine derivative) are described in Japanese Patent ProvisionalPublication Nos. 61(1986)-183640, 61(1986)-188535 and 61(1986)-228441,and Japanese Patent Application Nos. 60(1985)-210657, 60(1985)-226084,60(1985)-227527 and 60(1985)-227528. These reducing agents are alsodescribed in T. James, "The Theory of the Photographic Process", 4thedition, 291-334 (1977), Research Disclosure No. 17029, 9-15 (June1978), and Research Disclosure No. 17643, 22-31 (December 1978). Thereducing agents described in these publications and applications can beemployed in the light-sensitive material of the present invention. Thus,"the reducing agent(s)" in the present specification means to includeall of the reducing agents described in the above mentioned publicationsand applications.

These reducing agents can be used singly or in combination. In the casethat two or more reducing agents are used in combination, certaininteractions between these reducing agents may be expected. One of theinteractions is for acceleration of reduction of silver halide (and/oran organic silver salt) through so-called superadditivity. Otherinteraction is for a chain reaction in which an oxidized state of onereducing agent formed by a reduction of silver halide (and/or an organicsilver salt) induces or inhibits the polymerization of the polymerizablecompound via oxidation-reduction reaction with other reducing agent.Both interactions may occur simultaneously. Thus, it is difficult todetermine which of the interactions has occurred in practical use.

Examples of these reducing agents include pentadecylhydroquinone,5-t-butylcatechol, p-(N,N-diethylamino)phenol,1-phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidone,1-phenyl-4-methyl-4-heptadecylcarbonyloxymethyl-3-pyrazolidone,2-phenylsulfonylamino-4-hexadecyloxy-5-t-octylphenol,2-phenylsulfonylamino-4-t-butyl-5-hexadecyloxyphenol,2-(N-butylcarbamoyl)-4-phenylsulfonylaminonaphtol,2-(N-methyl-N-octadecylcarbamoyl)-4-sulfonylaminonaphthol,1-acetyl-2-phenylhydrazine, 1-acetyl-2-(p- or o-aminophenyl)hydrazine,1-formyl-2-(p- or o-aminophenyl)hydrazine, 1-acetyl-2-(p- oro-methoxyphenyl)hydrazine, 1-lauroyl-2-(p- or o-aminophenyl)hydrazine,1-trityl-2-(2,6-dichloro-4-cyanophenyl)hydrazine,1-trityl-2-phenylhydrazine, 1-phenyl-2-(2,4,6-trichlorophenyl)hydrazine,1-{2-(2,5-di-tert-pentylphenoxy)butyloyl}-2-(p- oro-aminophenyl)hydrazine, 1-{2-(2,5-di-t-pentylphenoxy)butyloyl}-2-(p-oro-aminophenyl)hydrazine pentadecylfluorocaprylate salt, 3-indazolinone,1-(3,5-dichlorobenzoyl)-2-phenylhydrazine,1-trityl-2-[{(2-N-butyl-N-octylsulfamoyl)-4-methanesulfonyl}phenyl]hydrazine,1-{4-(2,5-di-tert-pentylphenoxy)butyloyl}-2-(p-oro-methoxyphenyl)hydrazine,1-(methoxycarbonylbenzohydryl)-2-phenylhydrazine,1-formyl-2-[4-{2-(2,4-di-tert-pentylphenoxy)butylamido}phenyl]hydrazine,1-acetyl-2-[4-{2-(2,4-di-tert-pentylphenoxy)butylamide}phenyl]hydrazine,1-trityl-2-[{2,6-dichloro-4-(N,N-di-2-ethylhexyl)carbamoyl}phenyl]hydrazine,1-(methoxycarbonylbenzohydryl)-2-(2,4-dichlorophenyl)hydrazine and1-trityl-2-[{2-(N-ethyl-N-octylsulfamoyl)-4-methanesulfonyl}phenyl]hydrazine.

The amount of the reducing agent in the light-sensitive layer preferablyranges from 0.1 to 1,500 mole % based on the amount of silver (containedin the above-mentioned silver halide and an organic silver salt).

There is no specific limitation with respect to the polymerizablecompound, and any known polymerizable compounds including monomers,oligomers and polymers can be contained in the light-sensitive layer. Inthe case that heat development (i.e., thermal development) is utilizedfor developing the light-sensitive material, the polymerizable compoundshaving a relatively high boiling point (e.g., 80° C. or higher) that arehardly evaporated upon heating are preferably employed. In the case thatthe light-sensitive layer contains a color image forming substance, thepolymerizable compounds are preferably cross-linkable compounds havingplural polymerizable groups in the molecule, because such cross-linkablecompounds favorably serve for fixing the color image forming substancein the course of polymerization hardening of the polymerizablecompounds.

The polymerizable compound employable for the light-sensitive materialare described in the above-mentioned and later-mentioned publicationsand applications concerning the light-sensitive material.

Preferred polymerizable compounds employable for the light-sensitivematerial are compounds which are polymerizable through addition reactionor ring-opening reaction. Preferred examples of the compounds beingpolymerizable through addition reaction include compounds having anethylenic unsaturated group. Preferred examples of the compounds beingpolymerizable through ring-opening reaction include the compounds havingan epoxy group. Among them, the compounds having an ethylenicunsaturated group are preferred.

Examples of compounds having an ethylenic unsaturated group includeacrylic acid, salts of acrylic acid, acrylic esters, acrylamides,methacrylic acid, salts of methacrylic acid, methacrylic esters,methacrylamide, maleic anhydride, maleic esters, itaconic esters,styrene, styrene derivatives, vinyl ethers, vinyl esters, N-vinylheterocyclic compounds, allyl ethers, allyl esters, and compoundscarrying a group or groups corresponding to one or more of thesecompounds.

Concrete examples of the acrylic esters include n-butyl acrylate,cyclohexyl acrylate, 2-ethylhexyl acrylate, benzyl acrylate, furfurylacrylate, ethoxyethoxy acrylate, dicyclohexyloxyethyl acrylate,nonylphenyloxyethyl acrylate, hexanediol diacrylate, butanedioldiacrylate, neopentylglycol diacrylate, trimethylolpropane triacrylate,pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate,diacrylate of polyoxyethylenated bisphenol A, polyacrylate ofhydroxypolyether, polyester acrylate, and polyurethane acrylate.

Concrete examples of the methacrylic esters include methyl methacrylate,butyl methacrylate, ethylene glycol dimethacrylate, butanedioldimethacrylate, neopentylglycol dimethacrylate, trimethylolpropanetrimethacrylate, pentaerythritol trimethacrylate, pentaerythritoltetramethacrylate, and dimethacrylate of polyoxyalkylenated bisphenol A.

The polymerizable compounds can be used singly or in combination of twoor more compounds. Further, compounds formed by bonding a polymerizablegroup such as a vinyl group or a vinylidene group to a reducing agent ora color image forming substance are also employed as the polymerizablecompounds. The light-sensitive materials employing these compounds whichshow functions as both the reducing agent and the polymerizablecompound, or of the color image forming substance and the polymerizablecompound are included in embodiments of the invention.

The amount of the polymerizable compound for incorporation into thelight-sensitive layer preferably ranges from 5 to 1.2×10⁵ times (byweight) as much as the amount of silver halide, more preferably from 10to 1×10⁴ times as much as the silver halide.

Various embodiments of the light-sensitive materials, optionalcomponents which may be contained in the light-sensitive layer, andauxiliary layers which may be optionally arranged on the light-sensitivematerials are described below.

The polymerizable compound is preferably dispersed in the form of oildroplets in the light-sensitive layer. Other components in thelight-sensitive layer, such as silver halide, the reducing agent, thecolor image forming substances may be also contained in the oildroplets.

The oil droplets of the polymerizable compound are preferably preparedin the form of microcapsules. There is no specific limitation onpreparation of the microcapsules. There is also no specific limitationon shell material of the microcapsule, and various known materials suchas polymers which are employed in the conventional microcapsules can beemployed as the shell material. The mean size of the microcapsulepreferably ranges from 0.5 to 50 μm, more preferably 1 to 25 μm, mostpreferably 3 to 20 μm.

The light-sensitive layer can further contain optional components suchas color image forming substances, sensitizing dyes, organic silversalts, various kinds of image formation accelerators, thermalpolymerization inhibitors, thermal polymerization initiators,development stopping agents, fluorescent brightening agents,discoloration inhibitors, antihalation dyes or pigments, antiirradiationdyes or pigments, matting agents, antismudging agents, plasticizers,water releasers and binders.

There is no specific limitation with respect to the color image formingsubstance, and various kinds of substances can be employed. Thus,examples of the color image forming substance include both coloredsubstance (i.e., dyes and pigments) and non-colored or almostnon-colored substance (i.e., color former or dye- or pigment-precursor)which develops to give a color under application of external energy(e.g., heating, pressing, light irradiation, etc.) or by contact withother components (i.e., developer). The light-sensitive material usingthe color image forming substance is described in Japanese PatentProvisional Publication No. 61(1986)-73145.

Examples of the dyes and pigments (i.e., colored substances) employablein the invention include commercially available ones, as well as variousknown compounds described in the technical publications, e.g., YukiGosei Kagaku Kyokai (ed.), Handbook of Dyes (in Japanese, 1970) andNippon Ganryo Gijutsu Kyokai (ed.), New Handbook of Pigments (inJapanese, 1977). These dyes and pigments can be used in the form of asolution or a dispersion.

Examples of the substances which develop to give a color by certainenergy includes thermochromic compounds, piezochromic compounds,photochromic compounds and leuco compounds derived from triarylmethanedyes, quinone dyes, indigoid dyes, azine dyes, etc. These compounds arecapable of developing a color by heating, application of pressure,light-irradiation or air-oxidation.

Examples of the substances which develop to give a color in contact withother components include various compounds capable of developing a colorthrough some reaction between two or more components, such as acid-basereaction, oxidation-reduction reaction, coupling reaction, chelatingreaction, and the like. Examples of such color formation systems aredescribed in Hiroyuki Moriga, "Introduction of Chemistry of SpecialityPaper" (in Japanese, 1975), 29-58 (pressure-sensitive copying paper),87-95 (azo-graphy), 118-120 (heat-sensitive color formation by achemical change) or in MSS. of the seminer promoted by the Society ofKinki Chemical Industry, "The Newest Chemistry of Coloring Matter -Attractive Application and New Development as a Functional ColoringMatter", 26-32 (June, 19, 1980). Examples of the color formation systemsspecifically include a color formation system used in pressure-sensitivepapers, etc., comprising a color former having a partial structure oflactone, lactam, spiropyran, etc., and an acidic substance (developer),e.g., acid clay, phenol, etc.; a system utilizing azo-coupling reactionbetween an aromatic a diazonium salt, diazotate or diazosulfonate andnaphthol, aniline, active methylene, etc.; a system utilizing achelating reaction, such as a reaction between hexamethylenetetramineand a ferric ion and gallic acid, or a reaction between aphenolphthalein-complexon and an alkaline earth metal ion; a systemutilizing oxidation-reduction reaction, such as a reaction betweenferric stearate and pyrogallol, or a reaction between silver behenateand 4-methoxy-1-naphthol, etc.

The color image forming substance in the light-sensitive material ispreferably used in an amount of from 0.5 to 50 parts by weight, and morepreferably from 2 to 30 parts by weight, per 100 parts by weight of thepolymerizable compound. In the case that the developer is used, it ispreferably used in an amount of from about 0.3 to about 80 parts byweight per one part by weight of the color former.

There is no specific limitation with respect to the sensitizing dyes,and known sensitizing dyes used in the conventional art of photographymay be employed in the light-sensitive material. Examples of thesensitizing dyes include methine dyes, cyanine dyes, merocyanine dyes,complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes,hemicyanine dyes, styryl dyes, and hemioxonol dyes. These sensitizingdyes can be used singly or in combination. Combinations of sensitizingdyes are often used for the purpose of supersensitization. In additionto the sensitizing dyes, a substance which does not per se exhibitspectral sensitization effect or does not substantially absorb visiblelight but shows supersensitizing activity can be used. The amount of thesensitizing dye to be added generally ranges from about 10⁻⁸ to about10⁻² mol per 1 mol of silver halide. The sensitizing dye is preferablyadded during the stage of the preparation of the silver halide emulsion.

When the heat development is employed in the use of the light-sensitivematerial, an organic silver salt is preferably contained in thelight-sensitive material. It can be assumed that the organic silver salttakes part in a redox reaction using a silver halide latent image as acatalyst when heated to a temperature of 80° C. or higher. In such case,the silver halide and the organic silver salt preferably are located incontact with each other or close together. Examples of organic compoundsemployable for forming such organic silver salt include aliphatic oraromatic carboxylic acids, thiocarbonyl group-containing compoundshaving a mercapto group or an α-hydrogen atom, imino group-containingcompounds, and the like. Among them, benzotriazoles are most preferable.The organic silver salt is preferably used in an amount of from 0.01 to10 mol., and preferably from 0.01 to 1 mol., per 1 mol. of thelight-sensitive silver halide. Instead of the organic silver salt, anorganic compound (e.g., benzotriazole) which can form an organic silversalt in combination with an inorganic silver salt can be added to thelight-sensitive layer to obtain the same effect.

Various image formation accelerators are employable in thelight-sensitive material. The image formation accelerators have afunction to accelerate the oxidation-reduction reaction between a silverhalide (and/or an organic silver salt) and a reducing agent, a functionto accelerate emigration of an image forming substance from alight-sensitive layer to an image-receiving material or animage-receiving layer, or a similar function. The image formationaccelerators can be classified into inorganic bases, organic bases, baseprecursors, oils, surface active agents, hot-melt solvents, and thelike. These groups, however, generally have certain combined functions,i.e., two or more of the above-mentioned effects. Thus, the aboveclassification is for the sake of convenience, and one compound oftenhas a plurality of functions combined.

Various examples of these image formation accelerators are shown below.

Preferred examples of the inorganic bases include hydroxides of alkalimetals or alkaline earth metals; secondary or tertiary phosphates,borates, carbonates, quinolinates and metaborates of alkali metals oralkaline earth metals; a combination of zinc hydroxide or zinc oxide anda chelating agent (e.g., sodium picolinate); ammonium hydroxide;hydroxides of quaternary alkylammoniums; and hydroxides of other metals.Preferred examples of the organic bases include aliphatic amines (e.g.,trialkylamines, hydroxylamines and aliphatic polyamines); aromaticamines (e.g., N-alkyl-substituted aromatic amines,N-hydroxylalkyl-substituted aromatic amines andbis[p-(dialkylamino)phenyl]-methanes), heterocyclic amines, amidines,cyclic amidines, guanidines, and cyclic guanidines. Of these bases,those having a pKa of 7 or more are preferred.

The base precursors preferably are those capable of releasing bases uponreaction by heating, such as salts between bases and organic acidscapable of decarboxylation by heating, compounds capable of releasingamines through intramolecular nucleophilic substitution, Lossenrearrangement, or Beckmann rearrangement, and the like; and thosecapable of releasing bases by electrolysis. Preferred examples of thebase precursors include guanidine trichloroacetate, piperidinetrichloroacetate, morpholine trichloroacetate, p-toluidinetrichloroacetate, 2-picoline trichloroacetate, guanidinephenylsulfonylacetate, guanidine 4-chlorophenylsulfonylacetate,guanidine 4-methyl-sulfonylphenylsulfonylacetate, and4-acetylaminomethyl propionate.

These bases or base precursors are preferably used in an amount of notmore than 100% by weight, and more preferably from 0.1 to 40% by weight,based on the total solid content of the light-sensitive layer. Thesebases or base precursors can be used singly or in combination.

Examples of the oils employable in the invention include high-boilingorganic solvents which are used as solvents in emulsifying anddispersing hydrophobic compounds.

Examples of the surface active agents employable in the inventioninclude pyridinium salts, ammonium salts and phosphonium salts asdescribed in Japanese Patent Provisional Publication No. 59(1984)-74547;polyalkylene oxides as described in Japanese Patent ProvisionalPublication No. 59(1984)-57231.

The hot-melt solvents preferably are compounds which may be used assolvent of the reducing agent or those which have high dielectricconstant and can accelerate physical development of silver salts.Examples of the hot-melt solvents include polyethylene glycols,derivatives of polyethylene oxides (e.g., oleate ester), beeswax,monostearin and high dielectric constant compounds having --SO₂ --and/or --CO-- group described in U.S. Pat. No. 3,347,675; polarcompounds described in U.S. Pat. No. 3,667,959; and 1,10-decanediol,methyl anisate and biphenyl suberate described in Research Disclosure26-28 (December 1976). The light-sensitive material employing thehot-melt solvents is described in Japanese Patent Application No.60(1985)-227527. The hot-melt solvent is preferably used in an amount offrom 0.5 to 50% by weight, and more preferably from 1 to 20% by weight,based on the total solid content of the light-sensitive layer.

The thermal polymerization initiators employable in the light-sensitivematerial preferably are compounds that are decomposed under heating togenerate a polymerization initiating species, particularly a radical,and those commonly employed as initiators of radical polymerization. Thethermal polymerization initiators are described in "AdditionPolymerization and Ring Opening Polymerization", 6-18, edited by theEditorial Committee of High Polymer Experimental Study of the HighPolymer Institute, published by Kyoritsu Shuppan (1983). Examples of thethermal polymerization initiators include azo compounds, e.g.,azobisisobutyronitrile, 1,1'-azobis(1-cyclohexanecarbonitrile), dimethyl2,2'-azobisisobutyrate, 2,2'-azobis(2-methylbutyronitrile), andazobisdimethylvaleronitrile; organic peroxides, e.g., benzoyl peroxide,di-tert-butyl peroxide, dicumyl peroxide, tert-butyl hydroperoxide, andcumene hydroperoxide; inorganic peroxides, e.g., hydrogen peroxide,potassium persulfate, and ammonium persulfate; and sodiump-toluenesulfinate. The thermal polymerization initiators are preferablyused in an amount of from 0.1 to 120% by weight, and more preferablyfrom 1 to 10% by weight, based on amount of the polymerizable compound.In a system in which the polymerizable compound located in a portionwhere the latent image has not been formed is polymerized, the thermalpolymerization initiators are preferably incorporated into thelight-sensitive layer. The light-sensitive material employing thethermal polymerization initiators is described in Japanese PatentProvisional Publication No. 61(1986)-260241.

The development stopping agents employable in the light-sensitivematerial are compounds that neutralize a base or react with a base toreduce the base concentration in the layer to thereby stop development,or compounds that mutually react with silver or a silver salt tosuppress development. More specifically, examples of the developmentstopping agents include acid precursors capable of releasing acids uponheating electrophilic compounds capable of undergoing substitutionreaction with a coexisting base upon heating, nitrogen-containingheterocyclic compounds, mercapto compounds, and the like. Examples ofthe acid precursors include oxide esters described in Japanese PatentProvisional Publication Nos. 60(1985)-108837 and 60(1985)-192939 andcompounds which release acids through Lossen rearrangement described inJapanese Patent Provisional Publication No. 60(1985)-230133. Examples ofthe electrophilic compounds which induce substitution reaction withbases upon heating are described in Japanese Patent ProvisionalPublication No. 60(1985)-230134.

The antismudging agents employable in the light-sensitive materialpreferably are particles which are solid at ambient temperatures.Examples of the antismudging agents include starch particles describedin U.K. Patent No. 1,232,347; polymer particles described in U.S. Pat.No. 3,625,736; microcapsule particles containing no color formerdescribed in U.K. Patent No. 1,235,991; and cellulose particles, andinorganic particles, such as particles of talc, kaolin, bentonite,agalmatolite, zinc oxide, dititanium oxide or aluminum oxide describedin U.S. Pat. No. 2,711,375. Such particles preferably have a mean sizeof 3 to 50 μm, more preferably 5 to 40 μm. When the microcapsule isemployed in the light-sensitive material, the size of said particle ispreferably larger than that of the microcapsule.

Binders employable in the light-sensitive material preferably aretransparent or semi-transparent hydrophilic binders.

Examples of the binders include natural substances, such as gelatin,gelatin derivatives, cellulose derivatives, starch, and gum arabic; andsynthetic polymeric substances, such as water-soluble polyvinylcompounds e.g., polyvinyl alcohol, polyvinylpyrrolidone, and acrylamidepolymers. In addition to the synthetic polymeric substances, vinylcompounds dispersed in the form of latex, which are particularlyeffective to increase dimensional stability of photographic materials,can be also used. These binders can be used singly or in combination.The light-sensitive material employing a binder is described in JapanesePatent Provisional Publication No. 61(1986)-69062.

Examples and usage of the other optional components which can beobtained in the light-sensitive layer are also described in theabove-mentioned publications and applications concerning thelight-sensitive material, and in Research Disclosure Vol. 170, No.17029, 9-15 (June 1978).

Examples of auxiliary layers which are optionally arranged on thelight-sensitive material include an image-receiving layer, a heatinglayer, an antistatic layer, an anticurl layer and a release layer.

Instead of the use of the image-receiving material, the image-receivinglayer can be arranged on the light-sensitive material to produce thedesired image on the image-receiving layer of the light-sensitivematerial. The image-receiving layer of the light-sensitive material canbe constructed in the same manner as the layer of the image-receivinglayer. Examples and usage of the other auxiliary layers are alsodescribed in the above-mentioned publications and applicationsconcerning the light-sensitive material.

The light-sensitive material can be prepared, for instance, by thefollowing process.

The light-sensitive material is usually prepared by dissolving,emulsifying or dispersing each of the components of the light-sensitivelayer in an adequate medium to obtain coating solution, and then coatingthe obtained coating solution on a support.

The coating solution can be prepared by mixing liquid compositions eachcontaining a component of the light-sensitive layer. Liquid compositioncontaining two or more components may be also used in the preparation ofthe coating solution. Some components of the light-sensitive layer canbe directly added to the coating solution or the liquid composition.Further, a secondary composition can be prepared by emulsifying the oily(or aqueous) composition in an aqueous (or oily) medium to obtain thecoating solution.

The silver halide is preferably prepared in the form of a silver halideemulsion. Various processes for the preparation of the silver halideemulsion are known in the conventional technology for the preparation ofphotographic materials.

The silver halide emulsion can be prepared by the acid process, neutralprocess or ammonia process. In the stage for the preparation, a solublesilver salt and a halogen salt can be reacted in accordance with thesingle jet process, double jet process or a combination thereof. Areverse mixing method, in which grains are formed in the presence ofexcess silver ions, or a controlled double jet process, in which a pAgvalue is maintained constant, can be also employed. In order toaccelerate grain growth, the concentrations or amounts or the silversalt and halogen salt to be added or the rate of their addition can beincreased as described in Japanese Patent Provisional Publication Nos.55(1980)-142329 and 55(1980)-158124, and U.S. Pat. No. 3,650,757, etc.

The silver halide emulsion may be of a surface latent image type thatforms a latent image predominantly on the surface of silver halidegrains, or of an inner latent image type that forms a latent imagepredominantly in the interior of the grains. A direct reversal emulsioncomprising an inner latent image type emulsion and a nucleating agentmay be employed. The inner latent image type emulsion suitable for thispurpose is described in U.S. Pat. Nos. 2,592,250 and 3,761,276, JapanesePatent Publication No. 58(1983)-3534 and Japanese Patent ProvisionalPublication No. 57(1982)-136641, etc. The nucleating agent that ispreferably used in combination with the inner latent image type emulsionis described in U.S. Pat. Nos. 3,227,552, 4,245,037, 4,255,511,4,266,013 and 4,276,364, and West German Patent Provisional Publication(OLS) No. 2,635,316.

In the preparation of the silver halide emulsions, hydrophilic colloidsare advantageously used as protective colloids. Examples of usablehydrophilic colloids include proteins, e.g., gelatin, gelatinderivatives, gelatin grafted with other polymers, albumin, and casein;cellulose derivatives, e.g., hydroxyethyl cellulose, carboxymethylcellulose, cellulose sulfate, etc.; saccharide derivatives, e.g., sodiumalginate and starch derivatives; and a wide variety of synthetichydrophilic polymers, such as polyvinyl alcohol, polyvinyl alcoholpartial acetal, poly-N-vinylpyrrolidone, polyacrylic acid,polymethacrylic acid, polyacrylamide, polyvinylimidazole, andpolyvinylpyrazole, and copolymers comprising monomers constituting thesehomopolymers. Among them, gelatin is most preferred. Examples ofemployable gelatins include not only lime-processed gelatin, but alsoacid-processed gelatin and enzyme-processed gelatin. Hydrolysis productsor enzymatic decomposition products of gelatin can also be used.

In the formation of silver halide grains in the silver halide emulsion,ammonia, an organic thioether derivative as described in Japanese PatentPublication No. 47(1972)-11386 or sulfur-containing compound asdescribed in Japanese Patent Provisional Publication No. 53(1978)-144319can be used as a silver halide solvent. Further, in the grain formationor physical ripening, a cadmium salt, a zinc salt, a lead salt, athallium salt, or the like can be introduced into the reaction system.Furthermore, for the purpose of improving high or low intensityreciprocity law failure, a water-soluble iridium salt, e.g., iridium(III) or (IV) chloride, or ammonium hexachloroiridate, or awater-soluble rhodium salt, e.g., rhodium chloride can be used.

After the grain formation or physical ripening, soluble salts may beremoved from the resulting emulsion by a known noodle washing method ora sedimentation method. The silver halide emulsion may be used in theprimitive condition, but is usually subjected to chemical sensitization.Chemical sensitization can be carried out by the sulfur sensitization,reduction sensitization or noble metal sensitization, or a combinationthereof that are known for emulsions for the preparation of theconventional light-sensitive materials.

When the sensitizing dyes are added to the silver halide emulsion, thesensitizing dye is preferably added during the preparation of theemulsion as described in Japanese Patent Application No.60(1986)-139746. When the organic silver salts are introduced in thelight-sensitive microcapsule, the emulsion of the organic silver saltscan be prepared in the same manner as in the preparation of the silverhalide emulsion.

In preparation of the light-sensitive material, the polymerizablecompounds are used as the medium for preparation of the liquidcomposition containing another component of the light-sensitive layer.For example, the silver halide, (including the silver halide emulsion),the reducing agent, or the color image forming substance can bedissolved, emulsified or dispersed in the polymerizable compound toprepare the light-sensitive material. Especially, the color imageforming substance is preferably incorporated in the polymerizablecompound. Further, the necessary components for preparation of amicrocapsule, such as shell material can be incorporated into thepolymerizable compound.

The light-sensitive composition which is the polymerizable compoundcontaining the silver halide can be prepared using the silver halideemulsion. The light-sensitive composition can be also prepared usingsilver halide powders which can be prepared by lyophilization. Theselight-sensitive composition can be obtained by stirring thepolymerizable compound and the silver halide using a homogenizer, ablender, a mixer or other conventional stirring device.

Polymers having a principal chain consisting essentially of ahydrocarbon chain substituted in part with hydrophilic groups whichcontain, in their terminal groups, --OH or nitrogen having a loneelectron-pair are preferably introduced into the polymerizable compoundprior to the preparation of the light-sensitive composition. The polymerhas a function of dispersing silver halide or other component in thepolymerizable compound very uniformly as well as a function of keepingthus dispered state. Further, the polymer has another function ofgathering silver halide along the interface between the polymerizablecompound (i.e., light-sensitive composition) and the aqueous medium inpreparation of the microcapsule. Therefore, using this polymer, silverhalide can be easily introduced into the shell material of themicrocapsule.

The polymerizable compound (including the light-sensitive composition)are preferably emulsified in an aqueous medium to prepare the coatingsolution. The necessary components for preparation of the microcapsule,such as shell material can be incorporated into the emulsion. Further,other components such as the reducing agent can be added to theemulsion.

The emulsion of the polymerizable compound can be processed for formingshell of the microcapsule. Examples of the process for the preparationof the microcapsules include a process utilizing coacervation ofhydrophilic wall-forming materials as described in U.S. Pat. Nos.2,800,457 and 2,800,458; an interfacial polymerization process asdescribed in U.S. Pat. No. 3,287,154, U.K. Pat. No. 990,443 and JapanesePatent Publication Nos. 38(1963)-19574, 42(1967)-446 and 42(1967)-771; aprocess utilizing precipitation of polymers as described in U.S. Pat.Nos. 3,418,250 and 3,660,304; a process of using isocyanate-polyol wallmaterials as described in U.S. Pat. No. 3,796,669; a process of usingisocyanate wall materials as described in U.S. Pat. No. 3,914,511; aprocess of using urea-formaldehyde or urea-formaldehyde-resorcinolwall-forming materials as described in U.S. Pat. Nos. 4,001,140,4,087,376 and 4,089,802; a process of using melamine-formaldehyde resinshydroxypropyl cellulose or like wall-forming materials as described inU.S. Pat. No. 4,025,455; an in situ process utilizing polymerization ofmonomers as described in U.K. Pat. No. 867,797 and U.S. Pat. No.4,001,140; an electrolytic dispersion and cooling process as describedin U.K. Pat. Nos. 952,807 and 965,074; a spray-drying process asdescribed in U.S. Pat. No. 3,111,407 and U.K. Pat. No. 930,422; and thelike. It is preferable, though not limitative, that the microcapsule isprepared by emulsifying core materials containing the polymerizablecompound and forming a polymeric membrane (i.e., shell) over the corematerials.

When the emulsion of the polymerizable compound (including thedispersion of the microcapsule) has been prepared by using thelight-sensitive composition, the emulsion can be used as the coatingsolution of the light-sensitive material. The coating solution can bealso prepared by mixing the emulsion of the polymerizable compound andthe silver halide emulsion.

A light-sensitive material can be prepared by coating and drying theabove-prepared coating solution on a support in the conventional manner.

Use of the light-sensitive material is described below.

In the use of the light-sensitive material of the invention, adevelopment process is conducted simultaneously with or after imagewiseexposure.

Various exposure means can be employed in the imagewise exposure, and ingeneral, the latent image on the silver halide is obtained by imagewiseexposure to radiation including visible light. The type of light sourceand exposure conditions can be selected depending on the light-sensitivewavelengths determined by spectral sensitization or sensitivity ofsilver halide. Original image can be either monochromatic image or colorimage.

Development of the light-sensitive material can be conductedsimultaneously with or after the imagewise exposure. The development canbe conducted using a developing solution in the same manner as the imageforming method described in Japanese Patent Publication No.45(1970)-11149. The image forming method described in Japanese PatentProvisional Publication No. 61(1986)-69062 which employs a heatdevelopment process has an advantage of simple procedures and shortprocessing time because of the dry process. Thus, the latter method ispreferred as the development process of the light-sensitive material.

Heating in the heat development process can be conducted in variousknown manners. The heating layer which is arranged on thelight-sensitive material can be used as the heating means. The heatingtemperature for the development process usually ranges from 80° C. to200° C., and preferably from 100° C. to 160° C. Various heating patternsare applicable. The heating time is usually from 1 second to 5 minutes,and preferably from 5 seconds to 1 minute.

During the above development process, a polymerizable compound in aportion where a latent image of the silver halide has been formed or ina portion where a latent image of the silver halide has not been formedis polymerized. In a general system, the polymerizable compound in aportion where the latent image has been formed is polymerized. If anature or amount of the reducing agent is controlled, the polymerizablecompound in a portion where the latent image has not been formed can bepolymerized in the same manner as the light-sensitive material describedin Japanese Patent Provisional Publication No. 61(1986)-260241.

In the above development process, a polymer image can be formed on thelight-sensitive layer. A pigment image can be also obtained by fixingpigments onto the polymer image.

The image can be also formed on the image-receiving material. Theimage-receiving material is described hereinbelow. The image formingmethod employing the image-receiving material or the image-receivinglayer is described in Japanese Patent Provisional Publication No.61(1986)-278849.

Examples of the material employable as the support of theimage-receiving material include glass, paper, fine paper, coat paper,synthetic paper, baryta paper, metals and analogues thereof, polyester,acetyl cellulose, cellulose ester, polyvinyl acetal, polystyrene,polycarbonate, polyethylene terephthalate, and paper laminated withresin or polymer (e.g., polyethylene).

The image-receiving material is usually prepared by providing theimage-receiving layer on the support. The image-receiving layer can beconstructed according to the color formation system. In the cases that apolymer image is formed on the image-receiving material and that a dyeor pigment is employed as the color image forming substance, theimage-receiving material be composed of a simple support.

For example, when a color formation system using a color former anddeveloper is employed, the developer can be contained in theimage-receiving layer. Further, the image-receiving layer can becomposed of at least one layer containing a mordant. The mordant can beselected from the compounds known in the art of the conventionalphotography according to the kind of the color image forming substance.If desired, the image-receiving layer can be composed of two or morelayers containing two or more mordants different in the mordanting powerfrom each other.

The image-receiving layer preferably contains a polymer as binder. Thebinder which may be employed in the above-mentioned light-receivinglayer is also employable in the image-receiving layer.

The image-receiving layer can be composed of two or more layersaccording to the above-mentioned functions. The thickness of theimage-receiving layer preferably ranges from 1 to 100 μm, morepreferably from 1 to 20 μm.

After the development process, pressing the light-sensitive material incontact with the image-receiving material to transfer the polymerizablecompounds which is still polymerizable to the image-receiving material,a polymer image can be obtained in the image-receiving material. Theprocess for pressing can be carried out in various known manners. Thepressure in the process for pressing preferably ranges from 50 kg/cm² to1,000 kg/cm², more preferably ranges from 100 kg/cm² to 700 kg/cm².

In the case that the light-sensitive layer contains a color imageforming substance, the color image forming substance is fixed bypolymerization of the polymerizable compound. Then, pressing thelight-sensitive material in contact with the image-receiving material totransfer the color image forming substance in unfixed portion, a colorimage can be produced on the image-receiving material.

The light-sensitive material can be used for monochromatic or colorphotography, printing, radiography, diagnosis (e.g., CRT photography ofdiagnostic device using supersonic wave), copy (e.g., computer-graphichard copy), etc.

The present invention is further described by the following exampleswithout limiting the invention.

EXAMPLE 1 Preparation of Silver Halide Emulsion

In 1,000 ml of water were dissolved 20 g of gelatin and 3 g of sodiumchloride, and the resulting gelatin solution was kept at 75° C. To thegelatin solution, 600 ml of an aqueous solution containing 21 g ofsodium chloride and 56 g of potassium bromide and 600 ml of an aqueoussolution containing 0.59 mole of silver nitrate were addedsimultaneously at the same feed rate over a period of 40 minutes toobtain a silver chlorobromide emulsion having cubic grains, uniformgrain size distribution, a mean grain size of 0.35 μm and a bromidecontent of 80 mole %.

The emulsion was washed for desalting and then subjected to chemicalsensitization with 5 mg of sodium thiosulfate and 20 mg of4-hydroxy-6-methyl-1,3,3a,7-tetraazaindene at 60° C. to obtain thesilver halide emulsion. The yield of the emulsion was 600 g.

Preparation of Silver Benzotriazole Emulsion

In 3,000 ml of water were dissolved 28 g of gelatin and 13.2 g ofbenzotriazole, and the solution was kept at 40° C. while stirring. Tothe solution was added 100 ml of an aqueous solution of 17 g of silvernitrate over 2 min. An excessive salt was sedimented by pH-adjustmentand removed from the resulting emulsion. Thereafter, the emulsion wasadjusted to pH 6.30 to obtain a silver benzotriazole emulsion. The yieldof the emulsion was 400 g.

Preparation of Light-Sensitive Composition

In 100 g of pentaerythritol tetraacrylate were dissolved 0.40 g of thefollowing copolymer, 6.00 g of Pargascript Red I-6-B (tradename,Ciba-Geigy) and 2 g of Emulex NP-8 (tradename, preduced by NipponEmulsion Co., Ltd.). ##STR1##

In 18.00 g of the resulting solution was dissolved 0.002 g of thefollowing thiol derivative. To the solution was added a solution inwhich 0.16 g of the following reducing agent (I) and 1.22 g of thefollowing reducing agent (II) were dissolved in 1.80 g of methylenechloride. ##STR2##

Further, to the resulting solution were added 3.50 of the silver halideemulsion and 3.35 g of the silver benzotriazole emulsion, and themixture was stirred at 15,000 r.p.m. for 5 min. using a homogenizer toobtain a light-sensitive composition.

Preparation of Light-Sensitive Microcapsule

To 10.51 g of 18.6% aqueous solution of Isobam (tradename, produced byKuraray Co., Ltd.) was added 48.56 g of 2.89% aqueous solution ofpectin. After the solution was adjusted to pH 4.0 using 10% solution ofsulfuric acid, the light-sensitive composition was added to theresulting solution, and the mixture was stirred at 7,000 r.p.m. for 2min. using a homogenizer to emulsify the light-sensitive composition inthe aqueous medium.

To 72.5 g of the aqueous emulsion were added 8.32 g of 40% aqueoussolution of urea, 2.82 g of 11.3% aqueous solution of resorcinol, 8.56 gof 37% aqueous solution of formaldehyde, and 3.00 g of 8.00% aqueoussolution of ammonium sulfate in this order, and the mixture was heatedat 60° C. for 2 hours while stirring. After the mixture was adjusted toa pH of 7.3 using 10% aqueous solution of sodium hydroxide, 3.62 g of30.9% aqueous solution of sodium hydrogen sulfite was added to themixture to obtain a dispersion containing light-sensitive microcapsules.

Preparation of Light-Sensitive Material

To 10.0 g of the light-sensitive microcapsule dispersion were added 1.0g of 1% aqueous solution of the following anionic surfactant and 1.0 gof 10% solution (solvent: water/ethanol=50/50 volume ratio) of guanidinetrichroloacetate to prepare a coating solution. ##STR3##

The coating solution was uniformly coated on a paper (support (a):details are set forth in Table 1) using a coating rod of #40 to give alayer having a wet thickness of 70 μm and dried at about 40° C. toobtain a light-sensitive material (A).

EXAMPLE 2 Preparation of Light-Sensitive Material

Light-sensitive materials (B) and (C) were prepared in the same manneras in Example 1, except that the paper supports (b) and (c) set forth inTable 1 were used, respectively, in place of the support (a).

COMPARISON EXAMPLE 1 Preparation of Light-Sensitive Material

A light-sensitive material (D) was prepared in the same manner as inExample 1, except that the paper support (d) (details are set forth inTable 1) was used in place of the support (a).

COMPARISON EXAMPLE 2 Preparation of Paper Support

In a disk refiner, 70 parts of LBKP and 30 parts of NBKP were beated toobtain a pulp having a Canadian standard freeness of 350 cc. To theresulting pulp were added 5.0 parts of talc, 1.5 parts of rosin, 2.0parts of aluminium sulfate and 0.5 part ofpolyamide-polyamine-epichlorhydrin to obtain a paper stuff, in which thepart is a dry weight ratio to the pulp. A paper support (e) (details areset forth in Table 1) was made from the obtained paper stuff inFourdrinier paper machine.

Preparation of Light-Sensitive Material

A light-sensitive material (E) was prepared in the same manner as inExample 1, except that the paper support (e) was used in place of thesupport (a).

EXAMPLE 3 Preparation of Paper Support

In a disk refiner, 70 parts of LBKP and 30 parts of NBKP were beated toobtain a pulp having a Canadian standard freeness of 350 cc. To theresulting pulp were added 5.0 parts of talc, 1.5 parts of rosin, 2.0parts of aluminium sulfate and 0.5 part ofpolyamide-polyamine-epichlorhydrin to obtain a paper stuff, in which thepart is a dry weight ratio to the pulp. A fine paper having a basisweight of 69.0 g/m² was made from the obtained paper stuff inFourdrinier paper machine.

On the fine paper was coated a mixture of 100 parts of starch, 30 partsof polyvinyl alcohol and 400 parts of clay to give a layer having aweight of 15 g/m². Thus, a paper support (f) (details are set forth inTable 1) was obtained.

Preparation of Light-Sensitive Material

A light-sensitive material (F) was prepared in the same manner as inExample 1, except that the paper support (f) was used in place of thesupport (a).

                  TABLE 1                                                         ______________________________________                                        Support Kind of Paper                                                                              Basis Weight                                                                             Number of W.sub.CM *                          ______________________________________                                        (a)     Coat paper   84.9 g/m.sup.2                                                                           7                                             (b)     Cast-coated paper                                                                          84.9 g/m.sup.2                                                                           1-5                                           (c)     Synthetic paper                                                                            81.6 g/m.sup.2                                                                           1-5                                           (d)     Wood free paper                                                                            84.3 g/m.sup.2                                                                           91                                            (e)     Fine paper   84.0 g/m.sup.2                                                                           87                                            (f)     Coat paper   84.0 g/m.sup.2                                                                           6-7                                           ______________________________________                                         Remark:                                                                       "Number of W.sub.CM " means the number of the filtered maximum waviness o     not less than 4 μm, when the filtered maximum waviness is measured at      each of 100 positions according to the present invention.                

Preparation of Image-Receiving Material

To 125 g of water was added 11 g of 40% aqueous solution of sodiumhexametaphosphate, and were further added 34 g of zinc3,5-di-α-methylbenzylsalicylate and 82 g of 55% aqueous slurry ofcalcium carbonate, followed by coarsely dispersing in a mixer. Thecoarse dispersion was then finely dispersed in Dynomile dispersingdevice. To 200 g of the resulting dispersion were added 6 g of 50% latexof SBR (styrene-butadiene rubber) and 55 g of 8% aqueous solution ofpolyvinyl alcohol, and the resulting mixture was made homogenous.

The mixture was then uniformly coated on a cast-coated paper to give alayer having a wet thickness of 30 μm and dried to obtain animage-receiving material.

Evaluation of Light-Sensitive Material

Each of the light-sensitive materials prepared in Examples 1, 2 and 3and Comparison Examples 1 and 2 was uniformly exposed to light, using atungsten lamp at 60 lux for 1 second and then heated on a hot plate at125° C. for 40 seconds. Each of the exposed and heated light-sensitivematerials was then combined with the image-receiving material and passedthrough press rolls under pressure of 250 kg/cm² or 700 kg/cm² to obtaina magenta positive image on the image receiving material. The number ofthe low-density spots on the obtained image was observed with the nakedeye.

The results are set forth in Table 2. In Table 2, each of the valuerepresents number of the low-density spots observed with in the area of1 cm².

                  TABLE 2                                                         ______________________________________                                        Light-               Number of low-density spots                              Sensitive                                                                             Paper        (Pressure)                                               Material                                                                              Support      250 kg/cm.sup.2                                                                         700 kg/cm.sup.2                                ______________________________________                                        (A)     (a)          10-20     0-5                                            (B)     (b)          5-10      0-5                                            (C)     (c)          5-10      0-5                                            (D)     (d)          100-200   20-30                                          (E)     (e)          100-200   20-30                                          (F)     (f)          10-20     0-5                                            ______________________________________                                    

It is apparent from the results in Table 2 that each of thelight-sensitive materials (A), (B), (C) and (F) is remarkably reduced inthe occurrence of the low-density spot.

Further, a light-sensitive material employing a laminated paper (thesurface layer is a polyethylene film in which particles of titaniumdioxide are dispersed) as the support was also remarkably reduced in theoccurrence of the low-density spot.

I claim:
 1. A light-sensitive material comprising a light-sensitivelayer which contains a silver halide, a reducing agent and apolymerizable compound containing carbon to carbon unsaturation providedon a porous support, said silver halide and said polymerizable compoundbeing contained in microcapsules which are dispersed in thelight-sensitive layer, wherein the porous support has such a surfacecharacteristic that a filtered maximum waviness of not less than 4 μm isobserved in not more than 20 positions among 100 positions which aredetermined at random on a filtered waviness curve, the filtered maximumwaviness being determined within basic length of 2.5 mm extracted fromthe filtered waviness curve which is obtained from the profile of theporous support under the condition of the cut-off value of 0.8 mmaccording to JIS-B-0610.
 2. The light-sensitive material as claimed inclaim 1, wherein the porous support has such a surface characteristicthat a filtered maximum waviness of not less than 4 μm is observed innot more than 5 positions among 100 positions which are determined atrandom on the filtered waviness curve.
 3. The light-sensitive materialas claimed in claim 1, wherein the porous support has a thickness of notmore than 100 μm.
 4. The light-sensitive material as claimed in claim 1,wherein the porous support is a coated paper or a cast-coated paper. 5.The light-sensitive material as claimed in claim 1, wherein the poroussupport is a synthetic paper.
 6. The light-sensitive material as claimedin claim 1, wherein the light-sensitive layer further contains a colorimage forming substance.
 7. An image-forming method whichcomprises:imagewise exposing a light-sensitive material comprising alight-sensitive layer which contains silver halide, a reducing agent anda polymerizable compound containing carbon to carbon unsaturationprovided on a porous support, said silver halide and said polymerizablecompound being contained in microcapsules which are dispersed in thelight-sensitive layer, wherein the porous support has such a surfacecharacteristic that a filtered maximum waviness of not less than 4 μm isobserved in not more than 20 positions among 100 positions which aredetermined at random on a filtered waviness curve, the filtered maximumwaviness being determined within basic length of 2.5 mm extracted fromthe filtered waviness curve which is obtained from the profile of theporous support under the condition of the cut-off value of 0.8 mmaccording to JIS-B-0610; simultaneously or thereafter developing thelight-sensitive material to polymerize the polymerizable compound withinthe area where the latent image of the silver halide has been formed;and pressing the light-sensitive material on an image-receiving materialto transfer the unpolymerized polymerizable compound to theimage-receiving material.
 8. The image-forming method as claimed inclaim 7, wherein the development is done by a heat development process.9. The image-forming method as claimed in claim 7, wherein thedevelopment is done by a heat development process and the heattemperature in the heat development process is from 80° C. to 200° C.10. An image-forming method which comprises:imagewise exposing alight-sensitive material comprising a light-sensitive layer whichcontains silver halide, a reducing agent and a polymerizable compoundcontaining carbon to carbon unsaturation provided on a porous support,said silver halide and said polymerizable compound being contained inmicrocapsules which are dispersed in the light-sensitive layer, whereinthe porous support has such a surface characteristic that a filteredmaximum waviness of not less than 4 μm is observed in not more than 20positions among 100 positions which are determined at random on afiltered waviness curve, the filtered maximum waviness being determinedwithin basic length of 2.5 mm extracted from the filtered waviness curvewhich is obtained from the profile of the porous support under thecondition of the cut-off value of 0.8 mm according to JIS-B-0610;simultaneously or thereafter developing the light-sensitive material topolymerize the polymerizable compound within the area where the latentimage of the silver halide has not been formed; and pressing thelight-sensitive material on an image-receiving material to transfer theunpolymerized polymerizable compound to the image-receiving material.11. The image-forming method as claimed in claim 10, wherein thedevelopment is done by a heat development process.
 12. The image-formingmethod as claimed in claim 10, wherein the development is done by a heatdevelopment process and the heat temperature in the heat developmentprocess is from 80° C. to 200° C.
 13. The image-forming method claimedin claim 7, wherein the image-receiving material comprises animage-receiving layer provided on a paper support.
 14. The image-formingmethod claimed in claim 10, wherein the image-receiving materialcomprises an image-receiving layer provided on a paper support.